"Sie mag (Accusative Adjective)->jede (Feminien and has no article 'die/ein' is present)Zeitung." Look at the table in the link and decide what it will come for Jede.
lol, but "Sie liest jede Zeitung" is what I wrote in my previous comment! Instead, this exercise says: "Sie mag jede Zeitung", see the difference? That's why I wanted to know which would be the right way to say in German, "She reads all the papers although she doesn't like them all" (Sie liest jede Zeitung, obwohl sie nicht alle mag?)
Of course I'm not complaining, I have fun with sentences like this one. :-)
Well, "jede" = "every", and "alle" = "all". Saying that someone likes all newspapers (presumably all the newspapers that have ever existed) is not the same as saying someone likes every newspaper (which refers to either every newspaper there is or every newspaper in a set, or simply every newspaper this person has encountered).